Roofing material



United States Patent O ROOFIN G MATERIAL Joseph H. Bowman, Pittsburgh,Pa., assignor to American Steel Band Company, Pittsburgh, Pa., acorporation of Pennsylvania Application september 10, 19s4,`seria1Ne.455,260

s claims. (ci. s-1s) rl`his invention relates to the material used toform roofs, and more particularly to a roof that includes a sheet metaldeck covered with thermal insulation.

A common type of roof for industrial buildings is made of sheet metalwhich is covered with a thick layer of thermal insulation. Theinsulation, in turn, is protected by alternating layers of asphalt andtreated asbestos felt, and the top may be covered with fine gravel. Inthe past it has been the general practice to fasten the insulation tothe underlying metal deck by means of an intermediatelayer of asphalt.That is satisfactory for roofing purposes, but there have been cases inwhich a fire beneath the roof melts the asphalt so that it drips throughthe joints in `the deck and falls on the floor and machinery below,where it catches ire and adds materially to the conflagration.

It is among the objects of this invention to provide a roof in whichthermal insulation is attached to a supporting metal deck without theaid of asphalt or other inflammable material, and in which theconnection can be made quickly and securely.

In accordance with this invention, a sheet metal roof deck is providedwith laterally spaced, parallel folds projecting downward. A pluralityof U-shape sheet metal clips are inserted in some of the folds atlongitudinally spaced intervals. The clips are in frictional engagementwith the sides of the folds. A layer of thermal insulation covers themetal deck and is fastened to it by nails that are driven down throughthe insulation and into the clips. Since the sides of the folds resistopening of the clips, the folds press the sides of the clips tightlyagainst the nails to anchor them in the folds. Preferably, the upperportions of the side walls of each clip are Vfolded inwardly uponthemselves to form ribs extending lengthwise of the clip and havingsharp lower edges that dig into the adjoining nail or engage roughenedsurfaces on the nail. The insulation and the heads of the nails arecovered and protected by the usual layers of asphalt and roong felt.

The preferred embodiment of this invention is illustrated in theaccompanying drawings, in Which:

Fig. l is a fragmentary vertical section through my roof;

Fig. 2 is a fragmentary plan view thereof with the layers of asphalt androofing felt broken away;

Fig. 3 is an end view of one of the deck folds containing a clip; and

Fig. 4 is a vertical section through the fold and clip taken on the lineIV-IV of Fig. 3.

Referring to Fig. l of the drawings, the base of the roof is formed froma plurality of metal sheets 1 of a size that is convenient to handle.The sheets overlap along their sides and ends to form a metal deck thatrests on the usual beams (not shown Each deck sheet is bent lengthwiseto provide it with a number of laterally spaced parallel folds 2 thatproject downward at uniformly spaced intervals. One of these foldsextends along one edge of the sheet, While the opposite 2,895,432Patented July 2-1, 1,959

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edge is bent downward to fit into the edge fold of the sheet beside it.The space remaining in this edge fold, is lled with caulking compound 3to help seal the deck.` Each deck sheet preferably has its upper surfaceprotected against moisture by a thin layer 4| of asbestos that isimpregnated with a bituminous compound and bonded to the metal sheet.The amount of bituminous compound in this protective layer is so smallthat it will not drip from the roof in case there is a fire.

Disposed on top of the metal deck is a thick layer of thermal insulation6, such as rigid fiber type insulation.

This is laid after the deck has been anchored in place. Nothing is usedto stick the insulation to the deck, but the two are fastened togetherby means of nails 7 driven down through the insulation and into some ofthe folds .in the metal deck. Most suitably the nails extend throughlarge sheet metal washers S that engage the asphalt-impregnated covering9 that forms the upper surface off the insulation.

It is la feature of th-is invention that means are pror vided foranchoring the nails in the deck folds 2. Ac-

l portions of these side walls are folded inwardly on themselves to formribs 12 that extend lengthwise of the top of the clip. In other words,the upper portion of each side wall of the clip is twice the thicknessof the metal strip from which the clip is made. The shoulders 13 alongthe bottoms of the ribs have edges that are somewhat sharp. When theclips are made, the ribs are not pressed tightly together but are spacedand allowed to flare upwardly. Accordingly, when a clip is inserted inthe fold of a deck sheet the side walls of the clip are pinched nearlyclosed as shown in Fig. 3. Their tendency to spring apart holds the clipin tight engagement with the sides of the fold.

When a nail is driven down through the insulation above one of theseclips, the point of the nail enters the top of the clip between its ribsand spreads or bulges the clip apart. The clips are rather long, asshofwn in Figs. 2 and 4, so that it is not difficult for the nails tomeet them. Due to the clip ribs being some distance from the top of thedeck fold, the side walls of the fold likewise are bulged and thereforethe clip is held down in the fold. The resistance of the fold to bulgingholds the clip ribs tightly against opposite sides of the nail betweenthem, and the lower edges of the ribs tend to dig into the nail andanchor it in the clip. This effect is accentuated by using a nail havinga roughened or barbed lower end, which provides minute projections thatthe edges of the ribs can engage to hold the nail down.

After the insulation has been nailed to the deck securely in thismanner, the insulation is protected by the usual layers of asphalt andasphalt-impregnated asbestos felt. Thus, a layer of asphalt 15 isapplied to the top of the insulation and then a layer of felt 16 is laidon the asphalt. The roof can be built up in this manner as much asdesired. After the top layer of felt has been laid it is customary toapply a further layer of asphalt 17, on which fine gravel (not shown) issprinkled to form a fireproof covering.

In case there is -a re in a building having such a roof, overheating ofthe metal deck will not melt any roof asphalt which would penetrate theroof joints and drip into the building. Although layers of asphalt areused in the roof, they vwill be protected from the hot deck by theintervening thick layer of insulation. The result is that this roof doesnot become a hazard when there is a re, because it does not furnishasphalt that will feed the flames.

According to the provisions of the patent statues, I have explained theprinciple of my invention and have illustrated and described what I nowconsider to represent its best embodiment.V However, I desire to have itunderstood that, within the scope of the appended claims, the inventionmay be practiced otherwise than as specifically illustrated anddescribed.k

I claim:

l. The combination with a sheet metal roof deck provided with laterallyspaced parallel narrow folds projecting downward, and thermal insulationcovering the deck, of a plurality of thin U-shape sheet metal clipsdisposed at longitudinally spaced intervals in some of said folds infrictional engagement with their sides, each clip extending along a foldfar enough to'hold itself upright, and nails extending down through theinsulation and into said clips and forcing the sides of the clips apartagainst the resistance of the adjoining sides of the folds, whereby thenails are anchored in the folds to hold the insulation in place.

2. The combination with a sheet metal roof deck provided with laterallyspaced parallel narrow folds projecting downward, and thermal insulationcovering the deck, of a plurality of thin U-shape sheet metal clipsdisposed at longitudinally spaced intervals in some of said folds infrictional engagement with their sides, each clip extending along a foldfar enough to hold itself upright, and nails extending down through theinsulation and into said clips and forcing the sides of the clips apartagainst the resistance of the adjoining sides of the folds, the upperportions of the sidewalls of each clip being provided along their innersurfaces with ribs extending lengthwise thereof and pressed by the sidesof the supporting fold tightly against 4 the nail in the clip, wherebythe nails are anchored in the folds to hold the insulation in place.

3. The combination with a sheet metal roof deck provided with laterallyspaced parallel narrow folds projecting downward, and thermal insulationcovering the deck, of a plurality of thin U-shape sheet metal clipsdisposed at longitudinally spaced intervals in some of said folds infrictional engagement with their sides, each clip extending along a foldfar enough to hold itself upright, nails extending down through theinsulation and into said clips and forcing the sides of the clips apartagainst the resistance of the adjoining sides of the folds the upperportions of the sidewalls of each clip being folded inwardly intoengagement with themselves to form ribs extending lengthwise of the clipand having sharp lower edges, and the sides of the folds pressing theribs of the clips therein tightly against the nails, whereby the nails lare anchored in the folds to hold the insulation in place.

References Cited in the le of this patent UNITED STATES PATENTS

